Change speed transmission



ATTORNEY.

E W m M U z w H W W. T. LIVERMORE CHANGE SPEED TRANSMISSION Filed March 12, 1934 QQN Mm a Dec. 28, 1937.

w; T. LIVERMORE CHANGE SPEED TRANSMISSION Dec. 28, 1937.

Filed March 12, 1934 9 Shets-Sheet 2 Dec. 28, 1937.- w. 'r. LIVERMORE CHANGE SPEED TRANSMISSION Filed March 12, 1934 9 Sheets-Sheet 3 17/1/14 w ng INVENTOR; BY mam/7 rz/vmMa/FE E I ATTORN.

"Dec. 28, 1937. w. T. LIVERMORE CHANGE SPEED TRANSMISSION Filed March 12, 1934 9 Sheets-Sheet 5 Dec. 28, v 1937.

w. T. LIVERMORE 03,540

CHANGE SPEED TRANSMISSION F-i-led March 12, 1934 9 Sheets-Sheet 6 INVEN TOR. w/u/AM' Z'L/VE/FMORE ATTORNE Dec'. 28, 1937. w. r. LIVERMORE CHANGE SPEED TRANSMISSION INVENTOR.

Jul/W I LIME/705E BY ATTORNEY.

Dec. 28, 1937. w. T. LIVERMORE 2,103,540

CHANGE SPEED TRANSMISSION Filed March 12,1934 9 Sheets-Sheet 9 WILL/A17 T LIVE/MORE &

ATTORNEY.

f7 55 INVENTOR.

Patented Dec. 28, 1937 UNITED STATES PATENT OFFICE Application March 12,

27 Claims.

This invention relates to automatic speed change transmissions for automobiles and has for its principal object to provide a new and improved, highly eflicient, automatic transmission of marked simplicity having a minimum number of parts, so designed and constructed as to be particularly well adapted for manufacture at a relatively low cost by the high speed production methods used in the automotive industry. The present invention represents an improvement upon the transmissions and control systems disposed in my co-pending applications for United States Letters Patent, Serial 401,532, 584,812 and 603,823.

In its broadest aspects the present invention depends upon the automatic selection of the particular driving ratio between the engine and propellershaft by the combination of the extent of the throttle opening and the speed of the vehicle, the driving ratio at any instant being efiected through a selective transmission somewhat similar to the transmissions in common use in the automotive industry and being made operative by a fluid pressure controlled clutch. There is however, this fundamental difference between the transmission gearing of the present invention and that of the conventional selective sliding gear transmission, in that in the present invention all of those gears which efiect forward drive of the vehicle are constantly in mesh and the particular gears which efiect the different gear ratios are made operative or inoperative by the use of a fluid pressure operated clutch, as above referred to, there being one of such clutches for each gear ratio.

One of the principal objects of the present invention is to construct an automatic transmission of the type set forth with the transmission gearing, the fluid pressure controlled clutches, the pump for generating the fluid pressure for operating the clutches, and the valves and other control devices of the fluid pressure system, all

, arranged in a compact unit of relatively small dimensions so that it can be readily installed upon existing standard types of automobiles.

- Another object is to provide an automatic transmission for automotive vehicles that will operate smoothly and quietly, and without efiort, or without the necessity of skillful manipulation on ,the part of the driver, will automatically place into operative condition the proper gear ratio for driving conditions when the speed of the vehicle is either accelerating or decelerating andin which, moreover, provision is made in-. stantlyto interrupt the automatic operation whenever desirable by very simple manual controls readily'accessible to'the driver. I

t Afurther objectisjto provide dampingmeans between the engine shaft and driving shaft of the transmission that .will effectively absorb any Nos.

1934; Serial No. 715,065

sudden jerks or shocks being transmitted from the engine to transmission or vice versa.

Another object is to provide a change speed transmission especially adapted for automotive vehicles in which the gears for the different forward speedgear ratios are continually in mesh and the highly objectionable features resulting from the necessity of shifting gears into and out of mesh are obviated.

A further object is to construct a transmission of the type disclosed in which a single countershaft carries the clutch and gears for first or low speed drive and also the gears for second speed drive and in which part of the gears employed for second speed are also used for first speed transmission of the drive from the countershaft to the driving shaft.

Another object is to employ the transmission countershaft for driving a fiuidpressure pump which supplies fluid under pressure for operating the piston and cylinders which actuate the clutches for the difierent gear ratios, and to use said countershaft and pump as the fluid pressure piston for the low gear clutch.

A further object is to house the clutches for the second and third gear drives in a single clutch housing and to provide means whereby either of said clutches may be placed into or out of driving relationship by movement of said clutch housing.

Another object is to so construct the transmission and arrange the bearing members of the main driving shaft that the latter will be amply supported and braced against distortion by a plu-- rality of bearing members which form in effect a conical bracing system.

A further object is to provide the main driving shaft with means to prevent the transmission of end thrust due to the operation of the second and high gear clutches carried thereby, from said shaft to the engine or propeller shafts.

Another object is to provide a speed governor of simple, compact and effective design particularly well adapted for use with a transmission of the type set forth.

A further object is to employ certain members of the transmission gears for thediiferent speed ratios to drive the fluid pressure pump whenever the engine is rotating and other members thereof to drive the speed governor'at a rate proportional to the speed of the vehicle.

Another object is to provide the fluid pressure system with an automatically operating valve of simple construction for emciently maintaining matically established when the throttle 'accelerator pedal is released, and in which free wheeling can be locked out whenever desired, and also to release the clutches to provide a free wheeling condition automatically at low speeds thereby to prevent stalling of the engine when bringing the car to a stop.

The above and many other objects, such as simplicity of construction, low manuiacturing costs, compact, sturdy design of the device as a whole, as well as of its component parts, will appear more fully to those skilled in the art to which the invention appertains from the following more detailed description and by reference to the accompanying drawings forming a part hereof wherein a satisfactory constructional example is shown as illustrating the principles of the invention.

In order that the invention may be more readily understood the general scheme of construction and the nature of the principal component parts will be briefly outlined before proceeding with the detailed description.

In the drawings Fig. 1 is a central horizontal section through a transmission constructed in accordance with the present invention. Figs. 2 and 3 are sections on the lines 22 and 3-4 of Fig. 1 respectively.

Figs. 4, 5 and 6 are sections on the lines 4-4, 5-5 and 86 of Fig. 3.

Fig. 'l is a section on the line l--"l of Fig. 5. a

Fig. 8 is a section on the line 88 of Fig. 6.

Figs. 9, 10 and 11 are sections on the lines 9-9, Ill-l0 and l|--l| of Fig. 1.

Fig. 12 is a section on the line l2-l2 of Fig. 11.

Fig. 13 is a side elevation, partly broken away and partly in section, showing the manner of supporting the rear end of the transmission unit from the frame work of an automobile.

Fig. 14 is a section on the line ll-ll of Fig. 13.

Fig. 15 is a'section on the line i5-l5 of Fig. 13, and showing the construction of a braking means on'the propeller shaft of an automobile.

Fig. 16 is a section on the line l6l6 of Fig. 15.

Fig. 17 is a section on the line I 'I-l'l of Fig. 4.

Fig. 18 is a side elevation showing a means for rendering the transmission eflective under emergency conditions, such for example, as when a failure of the electric starter makes it desirable to start the engine by towing the car, this being efiected through the manipulation of parts connected with the conventional hand or emergency brake lever of an automobile, the said lever being shown broken away.

Fig. 19 is a diagrammatic view to illustrate the general layout of the principal component parts of the fluid pressure system with the connecting conduits between such parts and Fig. 20 is another diagram to illustrate the manner in which the functions of throttle opening and vehicle speed are co-operatively employed to effect the various speed gear ratios.

Fig. 21 is a sectional view of the governor taken on the line 2l2l of Fig. 9.

Fig. 22 is a diagrammatic view showing the modification in which means are provided for automatically closing the throttle during the change-over from one speed gear ratio to another.

Fig. 23 is a fragmentary sectional view of a modified form of the selector valve, the showing corresponding to the showing of such valve in m Fig. 24 is a section on the line Il-ll of Fig. 23.

Fig. 25 is aviewsimilartol'ig.23 of the pressure unloading valve, and

quite wide.

Fig. 26 is a section on the line 26-26 of Fig. 25.

The general nature of the invention will best be understood by reference first to the diagrammatic view of Fig. 19 in which the reference character P indicates a pump driven from the engine for pumping fluid under pressure to the various fluid operated clutches presently to be more fully described. The inlet side of the pump P is connected with a reservoir or sump R. Connected to the outlet side of the pump and interposed between said outlet and the main control valves of the system is an unloading valve U, the construction and operation of which will hereinafter be more fully set forth. The fluid from the pump passes through said unloading valve under conditions which will hereinafter be more fully described, and thence passes by the conduit C to a pressure control valve PV from which said fluid passes through the conduit C to a selector valve S to be directed, according to the setting of the valve, to the cylinders and pisto' s, designated Pi, P2, and P3, which actuate the clutches for the first gear, second gear and third gear forward drives respectively.

The selector valve S is provided with a longitudinally'extending conduit which is at all times in communication with the conduit C through which the fluid under pressure is delivered to said valve. This longitudinally extending conduit communicates in turn at its lower end with an annular passage formed in the valve, which passage is adapted to communicate with the conduits leading to the cylinders and pistons Pl, P2 and P3, as will be readily understood from an inspection of Fig. 19. The selector valve is caused to he slid longitudinally through its casing to establish communication to said fluid pressure cylinders and pistons under the influence of a floating differential lever 30, the central part of which is connected to the slidable member of the selector valve by means of the valve rod 3|. One end of the lever 30 is connected by means of a small rod 32 and pivoted lever 33 with the accelerator pedal 34, or other means for controlling the extent of opening of the throttle of the automobile engine. At its other end the lever 30 is connected by lost motion means through the connecting rod 33 with a governor indicated by the reference character G, and which governor is driven at a speed proportional with the speed of the vehicle, as will hereinafter be more fully described.

It is one of the principal objects of the pres- ,ent invention to provide a construction in which the automatic change-over of the transmission through the various speed changes will simulate, as closely as possible, the shifting of the gears manually in a selective sliding gear transmission when the car is being driven by a proficient driver. For example, when a driver wishes to speed his car up as rapidly as possible from a standing start, the throttle is usually opened Under the conditions of wideopen throttle the shift is made from one gear to another at relatively higher speeds than when, due to car load or other conditions, the car is started and accelerated more slowly. Engine load or torque may be employed directly for automatic transmission control, by the use of torque responsive controlling devices, but as such devices are of complicated and expensive construction, I prefer to employ the extent, or variation, of throttle opening coupled with speed of the car to control the gear ratios, the extent of throttle opening at any given car speed being indicative of the engine torque.

For example, the shift from low gear to second gear should be made at higher speed when acceleratingthan when in decelerating, the shift is made througknthe same gears in the reverse direction. These desired results and the proper coordination of vehicle speed and throttle opening are effected by the use of the differential or floating lever 30, which functions in the same manner as described in my co-pending application, Serial No. 603,823 hereinbefore referred to, and the operation of which can best be understood by reference to the diagrammatic views of Figs. 19 and 20. As shown in Fig. 20, the plurality of incline lines indicate various possible positions of the floating differential lever 30. The three dots and circles arranged vertically one above the other at the middle of the figure represent the approximate locations of the center of the lever 30 in which the selector valve S will be in a position to establish communication to the various cylinders and pistons for effecting first gear drive, second gear drive and third gear drive respectively. At the left hand side of the figure, the extent of movement of the left hand end of the lever 30 of Fig. 19 is indicated,--from the closed position of thethrottle at the top, to the fully opened position at the bottom. Obviously the throttle may occupy any position between its fully closed and fully opened positions. At the right hand end of the figure is indicated the extent of movement of the lever 39 produced by the operation of the governor G in accordance with vehicle speed. As will be readily understood from a study of Fig. 20 variations of the two fac-v tors, viz: extent of throttle opening and vehicle speed will cause the floating lever 30 to occupy different positions and to move the selector valve through the valve rod 3| to establish communication with the conduits leading to the first gear,

.second gear and third gear cylinders and pistons.

In the diagrammatic showing, two positions 30 and 30* of the lever 30 are shown for-closed throttle. In the lower position 30 with throttle closed and engine idling, the central portion of the lever 30 lies in the region for establishing communication to the'first gear, but no fluid will flow to the first gear clutch until the accelerator pedal is depressed to open the throttle and also 'to actuate the control valve PV to opened position. When first gear is thus made operative the first gear connection will be maintained until, as the speed of the vehicle increases, the center of the floating lever reaches the region in which the selector valve will be moved to cause I a shiftover from first to second'gear, this shift taking place when accelerating at a vehicle speed of approximately eight miles per hour (as indicated at 3ll Fig. 20) under the assumed calibration or adjustment of the elements depicted ,in' the diagrammatic showing selected. For full opened position of the throttle, the shift from first gear to second gear would take place shortly after the right hand and of the lever, moving under the influence of the gov ernor G, reaches the line corresponding to the speed of 14.8 miles per hour; while the shift from second to high with full opened throttle would take place when a speed of 38.5 miles per hour has been reached. Obviously for different positions of throttle opening, the speed at which the shift from one gear ratio to another would take place will vary in accordance with the throttle opening.

when the speed of the car is decreasing it is desirable to shift from a higher to a lower gear at a lower car speed than when shifting from lower to higher gear in accelerating, consequently means are provided to insure the gear shifts from higher to lower ratios at lower speeds and such means consists in the provision of a lost motion connection between the end of the governor rod 35 and floating lever 30, and consisting of a pair of spaced nuts 36- adjustably secured on the rod 35 and between which the end of the lever 30 is interposed. In order to insure that the selector valve will be positively moved from one position to another, springs 35'' are interposed between the nuts 35' and the end of the lever 30, so that when the rod 35 is moved by the governor to cause a movement of the selector valve, the first action will be to compress one of the springs 35 and as soon as the pressure exerted by the spring on the floating lever is suflicient to overcome the holding effect of the spring pressed ball detent I52, the selector valve will be snapped toits next position. Throwing of the valve past such next position may be prevented by associating a dash pot D ,with one end of the movable member of the valve the dash pot preferably being connected by the pipe D with the line leading to the sump R.

It is of course important that the pressure of the fluid which actuates the cylinders and pistons to throw the clutches into operative engagement for establishing the various gear ratios, be maintained with reasonable accuracy between certain maximum and minimum pressures. While substantially uniform delivery pressures in any pump may be effected by the use of the usual spring loaded by-pass ball valves, the use of such valves are objectionable for a pump which operates more or less continuously because of the fact that when the by-pass valves are opened the fluid is always pumped through such valves under pressure as determined by the spring loading which represents the performance of work that is dissipated entirely in the production of objectionable heating effects on the fluid being pumped. The use of-such ball valves is obviated in the present, invention and undesirable heating effects are avoided by the use of the pressure unloading valve U. This valve comprises a spring loaded piston having the upper end thereof reduced and projecting into a pressure receiving chamber A which is in communication with the delivery or outlet side of the pump and receives the full pressure delivered by the pump. The lower end of the unloading valve U contacts with a compression spring H1, the compression pressure of which may be regulated by an adjustable 'screw 8, and the valve is normally held in its fully opened or closed position by means of a small spring pressed ball detent I20. Let it be assumedthat it is desired to maintain the pressure in the delivery line of the pump between 1'75 pounds per square inch and 200 pounds per square inch. The area of the small plunger of the unloading valve which projects into the pressure chamber A is relatively small so as to permit the use of a relatively weak spring III which may be ad- 'justed so as, in combination with the resistance of the detent I20, to prevent downward movement of the valve until the pressure in the chamber A tends to exceed 200 pounds per square inch If the spring loaded ball detent I20, for example, be strong enough to resist a force of 12% pounds per square inch exerted on the small end of the unloading valve and the screw II8 be adjusted to resist 187 pounds, it will therefore take a pressure of 200 pounds per square inch in the pressure chamber to move the valve downwardly. When the valve is moved downwardly, communication is established by the unloading valve between the pressure line of the pump an the conduit B which leads back to the 0119:8581? vcir or sump R, the fluid then being by-passed back to the inlet side of the pump. As the pressure in chamber A drops, the valve will not be moved upwardly until such pressure reaches 187 -12 or 1'75 pounds per square inch when the valve being moved upwardly by spring III communication will be established between the inlet side of the pump and the conduit C, all as will presently be more fully set forth in connection with the detailed description of the unloading valve U.

In order to avoid jerky clutch action, the pressure control valve PV is provided. As will be readily understood it is highly desirable to avoid instantly placing the full fluid pressure in communication with any cylinder and piston thus throwing any one of the clutches into operative engagement suddenly, as the sudden application of the clutch would result in very jerky functioning of the device. While bleeder and time controls have been resorted to for the gradual applicationof fluid pressure operated devices, such controls will not operate uniformly because a bleeder will always admit full pressure if held open continuously for any length of time. The construction and arrangement of the control valve PV, as hereinafter more fully set forth, is such that the fluid pressure delivered to any clutch at any instant is appropriately varied in accordance with the extent of throttle opening; low pressure and hence soft application for part throttle and full application for full or wide open throttle, thus, not only insuring better maneuvering performance, but preventing jerky clutch action under widely varying conditions of temperature, load and throttle openings. The pressure valve PV shown diagrammatically in Fig. 19 is designed to meet the above requirements. This valve briefly comprises an annular bushing I25 having connected to it one end of a connecting rod I30, the upper end of which terminates in an enlarged head against which abuts the lower end of the pressure valve loading spring I35, the upper end of said spring abutting against a bell crank lever I36. Connected at its upper end to the lever 33 of the accelerator pedal 34 is a push rod I31, the lower end of which engages with the said bell crank lever. When the accelerator pedal is depressed the push rod will exert a downward thrust upon the end of the bell crank lever I36 and tend to compress the pressure valve loading spring I35.

As the pressure unloading valve is intended to be actuated towards opened position by the depression of the accelerator pedal, it' is important that it will not present too great a resistance to the actuation of said pedal, therefore the valve bushing I25 is balanced against pressure within the valve chamber and as the end of the small rod I30 is the only part of the valve subject to unbalanced pressure, the total upward pressure exerted on such rod will be comparatively small and such pressure may be overcome by lowering of the spring I35 in accordance with the extent of movement of the accelerator pedal and therefore also with the extent of throttle opening. As small throttle openings require light clutch pressure for smooth engagement, and large throttle openings require more pressure to transmit full engine torque, the clutch pressure should vary with throttle opening. The skillful driver does this with his clutch v pedal, whereas this effect is obtained in the present-invention by the operation of the pressure control valve. In the closed throttle position, with the valve in the position shown, there is no pressure upon the spring I35. Consequently, any fluid pressure in the valve casing (or in any cylinder PI, P--2 or P3) will tend to raise the bushing I25 against the spring I35 and open the lower or exhaust port letting fluid flow back to the sump until the pressure is relieved. The valve will then return to the position shown in which both inlet and exhaust ports are closed.

When the throttle is opened and spring pressure proportional to throttle opening is exerted, this pushes the bushing I25 down, uncovering the upper or inlet port of conduit C, thus admitting fluid which builds up pressure within the valve casing and when it becomes equal to the spring pressure, again raises the valve to the position shown in which both ports are closed. The bushing I25 also comes back to the position shown when the fluid pressure equals the spring pressure. If the throttle is opened, the spring pushes the valve down admitting more oil. If it is closed, the spring pressure is diminished and the fluid pressure raises the valve and lets oil out at the lower or exhaust port until the balance is again established. Fluid pressure is thus kept proportional to throttle openmg.

In order to permit any clutch to be slipped into engagement during a gear change while preventing slippage during normal driving, the valve bushing I25 is of such length as to overlap the inlet and exhaust ports thereof when in neutral position. This in effect gives a limited lost motion between the beginning of the opening and closing positions of the valve, so that when the engine is idling the clutch may be slipped in but when driving, with throttle nearly closed at low speeds the valve will hold the pressure to maintain the clutch in non-slipping engagement at a more nearly closed throttle position than that at which the valve opened.

We will now proceed with the detailed description of the various parts of the apparatus and for convenience and clarity the apparatus will be described with the following headings and subheadings:

Main housing and transmission gearing including:

(11-) Direct drive (b) Second gear drive (0) First gear drive Fluid pressure system and valves thereof Reverse gear Vehicle speed governor control 7 Free wheeling lockout Second gear brake Manual operation I Transmission shaft brake Modified automatic throttle control Modified valve structures constructional and operative advantages.

The apparatus is containedwithin a housing (see Fig. 1) indicated generally by reference character Hand which-for convenience of fabrication and assembly preferablycomprises a plurality of housing sections 40, 4| and 42 suitably secured together; the housing ,secti n 49 at its front end preferably being bolted to the engine. At its rear end thehousing'H is supported by .meansof a bracket 43 (see Figs.

13 and 14) bolted to the underside of the hous ing section 42. Said bracket at its lower end may be of channel cross section, asshown at 49', to receive a block 44 of any suitable resilient material, such as rubber, which is interposed between said bracket and a transversely extending supporting frame member 46. At its central part the section 49' is provided with an upwardly projectlng lug 45 which seats within a recess formed in the bottom wall of the housing 42.

' 4 Located within the chamber formed by the housing section 49 is a fly wheel 41 (see Fig. 1) provided on one side with an annular rearwardly projecting flange 48, which defines a cup-shaped recess into which projects the clutch housing member 49 for the direct drive and second gear clutches. Suitably supported by a bearing 59, in the end of the engine shaft 5| is one end of a drive shaft 52, the other end of which shaft is supported within a bearing 50? and is adapted to be connected, by a conventional universal joint, a portion of which is indicated at 53, with the main or propeller shaft of an automobile.

The clutch housing 49 is provided with a hollow rearwardlyextending boss 54, the end of which abuts against a ball bearing 55, having its outer race fixed within suitable recesses in a pair of keys 56 slidabiy mounted on suitable keyways formed within the inner wall of the housing section 4|. The rear end of the housing section 49 has secured to it a member 51 provided with rearw-ardly extending hollow boss 58 which encircles the boss 54 of.the clutch housing 49 and forms therewith an oil seal, said boss 58 being provided with a spiral groove 58 which, when the boss 54 rotates, wipes the oil back into the gear casing. Theclutch housing 49 is secured to the fly wheel 41 for rotation therewith by means which prevent, and tend to absorb, any sudden shocks or jerks. Such means comprises a plurality of arcuate shaped blocks 59 (see Figs. 1 and 2) each of which is secured to the fly wheel 41 by means of a pair of studs 59 secured in the -fly wheel and projecting into holes in the arcuate blocks. Each of the arcuate blocks 59 is provided at each end with a suit-- able recess in which is received a cushioning spring 62, the ends of which springs abut against pins 63 suitablysecured to an annular flange 54- projecting laterally from the exterior of the clutch housing 49. Approximately midway between its ends each block 59 has secured in it the threaded end of a bolt 6| which passes through an elongated slot 69 in the flange 64 of the clutch housing. Threaded upon the other ends of the bolts 6| are nuts 65 which, form abutments for the springs 66 which serve to hold a pair of friction discs 65 with a yieldingpressure against said flange 64, and thus assist the springs 62 in damping sudden jerks or shocks, one of said discs 95'- being held in contacting engagement with (a) Direct drive (Fig. 1)

Situated within the clutch housing 49 are the clutches for direct and second gear drive. The

direct drive clutch comprises a clutch member 91 having a hollow central boss which is splined to l the drive shaft 52. The exterior of said boss is provided with a plurality of splines with which are engaged a plurality of clutch discs 88, interposed between clutch discs 59 splined at their outer periphery to the interior of the clutch housing 49. The clutch member 61 is provided at one end with a disc section B'I which forms at one end an abutment for the clutch discs 58, 59 and said clutch member Bl is secured against movement longitudinally of the shaft 52 by means of a. split ring Ill suitably seated within an annular recess provided in the shaft 52 and furnishing an abutment against which the clutch member 61 engages. way within the interior of the housing 49 is a second abutment plate H which is secured against longitudinal movement relatively to the clutch housing 49 by means of the split retaining rings 12 seated within suitable annular recesses formed in the inner cylindrical wall of the housing 49 and engaging the abutment plate II on each side thereof.

The application of the'direct drive clutch is effected by imparting a longitudinal movement to the clutch housing 49, from right to left in Fig. 1, by means presently to be more fully described. This longitudinal movement of the clutch ho'us ing is imparted to the abutment member H, and then successively in turn through the clutch discs 69 and 69 to the abutment plate 61* of the clutch member 61, the thrust of the clutch plates being transmitted directly to the shaft 52 through the retaining ring I0. When the clutch discs 68-89 are held in contacting engagement the drive is then transmitted, -in a manner which will be readily understood, directly from the fly Located substantially. midwheel 41 at engine speed to the shaft 52, tq be 0 carried directly through said shaft to the universal connection 53 of the propeller shaft of the Y vehicle.

(b) Second gear drive (Fig. 1),

The clutch housing 49 also contains the clutch for the second gear drive and this comprises a' clutch member 13 somewhat similar in construction to the clutch member 61 and having a central boss 13 splined or keyed to a hollow sleeve 14; the latter surrounding the shaft 52 in concentrically spaced relation thereto and extending rearwardly a considerable distance into the housing section 4|; said sleeve being rotatably supported in roller bearings 15-16 interposed beabuts and at its rear end said sleeve abuts against a ball bearing 88 held between a split ring 14 seated in a groove of shaft 52 and a shoulder formed on said shaft. When the clutch housing 49 is shifted longitudinally from left to right in Fig. 1, the clutch discs 1819 will be held in driving engagement and the rotation of the flywheel 41 will be impartedto the sleeve 14. At its extreme rearward end the sleeve 14 is provided with a cup-shaped recess for the reception of a ball bearing 88 interposed between said sleeve and the shaft 52. Immediately adjacent to, and in abutting relationship with the ball bearing 88, the sleeve 14 is provided with a gear 8|, the teeth of which mesh with a gear 82 formed on a sleeve 83 rotatably mounted upon the countershaft 84. roller bearings 85-85 being interposed between said countershaft and sleeve. The sleeve 83 has also formed upon it a gear 81 which meshes with a gear 88 keyed to driveshaft 52. When the sec- 0nd gear clutch plates "-19 are in driving engagement the drive will be transmitted from the fly wheel 41 to the clutch housing 49 and thence through the clutch discs 18, 19, the sleeve 14, gears 8|, 82, 81 and 88 to the drive shaft 52 and thence through the connection 53 to the propeller shaft.

As will be seen from an inspection of Fig. 1, the

gear reduction provided by the gears 8|, 82, 81 and 88 will effect the driving of the vehicle at the lower second speed gear ratio.

(0) First gear drive (Fig. 1)

The sleeve 11 above referred to is keyed to the rearwardly extending boss 54 of the clutch housing 49 by means of the keys 89 and consequently said sleeve 11 will be driven continuously at engine speed when the engine is operated. At its rearward end, the sleeve 11 is provided with a gear 98, which abuts against the face of the ball bearing 55 which it will be remembered is carried by the sliding keys 56. The clutch housing 49 and sleeve 11 are also secured together to move as a unitary structure both in longitudinal fore and aft movement by means of a dowel 11' threaded into the boss 54 and having at its inner end a teat which engages within a suitable hole in sleeve 11. The teeth of gear 98 mesh with the teeth of a gear 98'- splined upon the countershaft 84. At its rearward end, the shaft 84 is provided with a plurality of external splines with which are engaged the clutch discs 9| of the first gear clutch. These clutch discs 9| are interposed between clutch discs 92 splined at their periphery to the inner wall of a clutch housing 93. The housing 93 is provided with a central apertured boss 93 which projects forwardly and is splined to the countershaft sleeve 83, the housing 93 and sleeve 83 thereby forming a unitary structure which is rotatably mounted between a ball bearing 94,and the roller bearings 85, 86 hereinbefore described and located between the sleeve 83 and countershaft 84, the'latter also being supported by a ball bearing 95 interposed between the forward end of said shaft 84 and a bearing block 98 located within'a cylinder formed in the housing section 4|, while the ball bearing 94 is interposed between the sleeve 83 and a bearing boss 4| formed on the rear wall of the housing section 4|.

An abutment plate 91 for actuating the first gear clutch discs 9|, 92 is secured to the shaft 84 by means of a split retaining ring 98, and a second abutment plate 99 for said clutch is secured to the inner wall of the housing 93 by means of a ring I88. The movement of the clutch plates 9|, 92 into contacting engagement is effected by shifting the shaft 84 longitudinally by means which will presently be described.

In order to effect disengagement of the first gear clutch, a spring MI is seated within a recess formed in the rear end of the shaft 84 and said spring bears against a plug I82 slidably mounted in an adjustable screw cap I83 threaded into the end of said shaft 84. The plug I82 is provided with a reduced end which projects through a central aperture of said screw cap I83 and is adapted to engage with the abutment plate 99.

When the shaft 84 is shifted longitudinally from left to right to actuate the clutch discs 9|, 92 into driving engagement, the drive will be transmitted from the engine shaft through the fly wheel 41, clutch housing 49 to the sleeve 11, which it will be remembered is keyed directly by keys 89 to said clutch housing 49 and operates continuously at engine speed. The drive is then transmitted through the gears 98, 98 to the shaft 84, clutch plates 9| 92 to the clutch housing 93 and thence back through the sleeve 83 to rotate said sleeve at the same speed as the shaft 84; thence the drive passes through the gear 81 to the gear 88 to the driveshaft 52 and connection 53 thereof to the propeller shaft. It will be noted that although the same gears 81, 88 are employed for effecting drive to the driveshaft 52 for both first speed and second speed drive, first, speed drive is obtained from the countershaft 84 driven by the gears 98, 98', whereas second speed drive is effected directly through the sleeve 83 through the gears 8|, 82 and thence to the gears 81, 88. It will be seen that the gear reduction between the gears 98, 9| is considerably greater than that between the gears 8|, 82, hence low or first speed drive will be at a lower gear ratio.

When either first gear or direct drive is operative, the sleeve 83 and housing 93 will be rotated in accordance with the speed of the driving shaft and as said sleeve 83 is continuously geared with the sleeve 14 through the gears 8|, 82, the sleeve 14 vill of course be rotated but the rotation of the latter will be an idle or free rotation as said sleeve 14 is not connected in operative relation with either the engine or driving shaft 52 except when the second gear clutch is in engagement.

FLUID PRESSUBE SYSTEM AND VALVES Tnanaor (Figs. 1, 3, 4, 5, 6, 7, 8, 9 and 19) The forward end of the countershaft 84 is connected by a self-adjusting tang and groove connection I84 (see Figs. land 7) with a pump shaft I85 to which is keyed, or otherwise suitably secured, a rotary pump of the radial vane type. the constructional details of which form no part of the present invention. This pump, designated generally by the reference character P, is located within a cylindrical chamber I85, (see Figs. 1 and 3) formed within the housing section'4I. Communicating with the cylindrical chamber I88 is the outlet conduit I81 (Fig. 7) which leads to the pressure unloading valve U. The pump chamber I88 also communicates through the inlet conduit I88- (see Fig. 3) with the sump R. The pressure unloading valve U (see Figs. 5 and 7) is located in a valve casing I88 bolted to the side of the main housing section 4|, and consists of a valve plunger I89 slidably mounted within a chamber II8 formed in said valve casing. The valve plunger I88 has at one end thereof a reduced head III which projects into the pressure .eceiving chamber A formed in the casing I08. Intermediate its ends the valve plunger I09 is provided with an annular recess or groove II2 which is adapted to align with a pair of aligned ports 3, II3 in the wall of the chamber H0, and which communicate respectively with the outlet conduit I'I of the pump and the pressure receiving chamber A.

The plunger I09 is also provided at its'inner end with a longitudinal slot II4 which communicates with a bore II5 provided centrally of said plunger. At its other end the bore .5 of the plunger I09 is counterbored, as indicated at H6,

to receive a compression spring I", one end of" which abuts against the inner end of said counterbore and the other end of which abuts against an adjustable screw plug I I8. That end of the chamber I I0 of the unloading valve U adjacent the open end of counterbore I I6, communicates through the port I [9 with the oil receiving chamber or sump R...

As the pump P is connected to the countershaft 84 by the tank and groove connection I04, and as the countershaft 84 is continuously driven from the engine by the gears 90, 90 and the keyed connection of the sleeve 11 to the clutch housing 49, the'pump P will be rotated at all times when the engine is operating, and the fluid under pressure will be delivered by the pump through the outlet conduit I0'I thereof. With the unloading valve in the position shown in Fig. '7 of the drawings, the fluid will pass through the conduit I01 and port I13 around the annular groove II2. andthrough port II3 to the pressure receiving chamber A. The strength of the spring H1 and the pressure of the spring pressed ball detent I is so proportioned as to resist any inward movement of the valve plunger I09 until the pressure' within the chamber A exceeds the predetermined maximum, as hereinbefore described. Should the pressure exceed this maximum, the force exerted on the reduced end of III. of the valve plunger I09 will cause the plunger to be moved towards'the right in Fig. '1 and when the longitudinal slot 4 in the plunger comes into registry with the port I I3, the fluid under pressure from the "pump will be lay-passed through the bore II5, counterbore H6 and port II9 to the sump or oil receiving cham ber R.

Too rapid fluctuation of the plunger I09 is prevented by means of the spring pressed ball I20 (see Fig. 5) which is adapted to engage with a pair of recesses I2I and I22 provided in the outer periphery of the plunger I09and so arranged relatively to said ball as to hold the plunger I09 in the position shown in Fig. 7 in which communication is established between the pump and pressure receiving chamber A, or in the position in which communication is established between said pump and the sump R. Should the pressure within the pressure cham-. ber A tend to mount very rapidly, and thereby cause, the plunger I09 to be projected past the point of engagement of the recess I22 with the ball I20, such an action would be prevented by the stop bolt I23 which limits such outward movement of the plunger to the point where the recess I22will engage the ball I20.

In order to relieve the fluid pressure system of shocks resulting from variations in the fluid pressure, an air pressure chamber forming member I24 (seeFig. 6) is secured to the upper side of the housing I00 and is in communication with the pressure receiving chamber A, said air cham-L ber I24 functioning to provide a reserve supply to facilitate smooth clutching and a gradual increase of clutch pressure as the pump replenishes the supplyof fluid in said chamber.

The pressure control valve PV, hereinbefore briefly described, consists of a bushing I25 (see Figs. 6 and 8) slidably mounted in a cylindrical chamber I26 formed in the valve casing I08, which chamber communicates through the port I21 with the pressure receiving chamber A and through the port I28 with the sump or oil receiving chamber R. It also communicates through the port I29 (see Fig. 8) with the conduit C that leads to the selector valve.

V The bushing I25 has connected to it one end of a push rod I30, the other end of which abuts against one arm I3I of a bell crank lever which projects through the wall of the valve casing I08 and is provided with a second lever arm (not shown), from which suitable connection is made to the accelerator pedal through the interposition of the spring I35 and bell crank I36 shown in the diagrammatic view of Fig. 19. The spring I35, as hereinbefore described, abuts against the bell crank lever I 36 and the push rod I31 serves to transmit motion imparted to the accelerator pedal to open the throttle through the spring I35 and bell crank lever I3I to the push rod I30 of the pressure control valve. As before pointed out, the area of the rod I30 and the compression load upon the spring I are so proportioned that the. bushing I25 will, when the throttle is closed, be held by the fluid pressure within the system in'such position as to shut off communication between the intrior of the chamber I25 and the ports I21 and I28. When the accelerator is depressed to open the throttle valve of the engine, the extra'compression placed upon the spring I35 through the downward movement of the rod I31 will be sufficient to, overcome the unbalanced pressure upon the end of the small push rod I30, and the bushing I25 will therefore be moved to uncover the port I21 and establish communication through the chamber I26 to the port I29, which communicates with the conduit C leading to the selector valve.

As hereinbefore pointed outthepressure on' counteracting efiect produced by the loading of the spring .I35' by the depression of the ac-' celerator, the pressure within the valve chamber I26 will vary in accordance with the throttle opening. The pressure control valve being interposed between the selector valve and the pressure side of the pump, the pressure of the fluid delivered to any cylinder and piston can not therefore be greater than thatin the chamber I20 andin accordance with the extent of throttle opening.

The selector valve comprises a hollow sleeve or bushing I40 (see Figs. 5 and 8) slidably mounted within a cylindrical chamber I4I provided in the'valve casing I08. This sleeve I40 is provided on each side thereof with a longitudinally extending recess I42 which communicates at the one end with an annular recess I43 which is adapted to be brought into registry with the actuation of the clutches for first gear, second gear and high gear or direct drive respectively. The sleeve I40 is also provided with the ports I41, I48 and I48 which communicate through the wall of the sleeve with the hollow bore thereof and thence with the oil receiving chamber or sump R, as will be readily understood from an inspection of Figs. 7 and 8 of the drawings. Secured to one end of the selector valve is one arm of a bell crank lever I50 which lever is journaled in the side wall of the valve casing I08, and has an arm (not shown) on the exterior-of said casing to which is suitably connected the connecting rod 3| leading to the floating lever 30. In order to hold the selector valve with its ports in proper registry with the ports leading to the cylinders and pistons for actuating clutches for the various gears, the outer wall of the sleeve I40 is provided with a plurality of depressions II adapted to be engaged by the spring pressed ball I52. The low gear port I44 communicates with a conduit I44 that extends horizontally and terminates in the port I44 (Fig. '7) in the end of the cylinder I06 of the pump P. When the selectorvalve is in the position shown in Figs. 5, 8 and 19 of the drawings, fluid under pressure from the pump passes through the unloading valve U, conduit C, the pressure control valve PV, the elongated slot I42 of the selector valve and annular groove I43 thereof to the port I44, conduit I44 and port I44 in the end of the pump cylinder I06, and pressure will be exerted upon the end of the pump P to cause the same to be moved towards the right in Fig. 1. This movement of the pump will be communicated to the shaft 84 to cause it to be moved towards the right, carrying with it the abutment plate 81 of the low or first gear clutch and thus to cause the clutch plates 8|, 82 to be held in contacting driving engagement.

When the selector valve is moved, under the action of the floating differential lever 30, to bring the annular groove I43 of such valve into registry with the port I45 for second gear, the

fluid will pass through the port I45 to the conduit I55 to the cylinder and piston P-2 for actuating the clutch for second gear.

It will be remembered that engagement of the clutch for second gear and direct drive is effected by the longitudinal movement of the clutch housing 49 and that the end of the boss 54 of such clutch housing abuts against the ball bearing 55 which is carried in the sliding keys 56. The sliding keys 56 as shown in Fig. 1 are provided with the yoked portions I60, with which are engaged the ends of a clutch actuating yoke I6I. (Fig. 3.) The yoke I6I is formed integrally with or keyed to the bearing shaft I62 suitably journaled in the housing section M and said shaft carries at one end thereof a downwardly depending lever arm I63 the lower end of which is provided with a ball I64. This ball is located within a recess formed between the pistons of the cylinders and pistons P--2 and P--3 for second and high gear. The construction of each of these pistons is similar, both pistons preferably, for simplicity of manufacture, being constructed as one integral piece, and each consists of a piston member I65 (Fig. 4) slidably mounted within 'a cylinder I66 formed in the housing 4I. One end of each piston I65 is counterbored for the reception of a coil spring I61, a spring retaining cap I68 preferably being provided within the counterbore of the piston. This spring retaining cap has one end thereof swaged over the head end of a small rod I69, to the other end of which is secured a spring abutment member I which bears against the cylinder head I1I. When the piston I65 of the cylinder and piston P-2 is placed in communication with the fluid pressure through the conduit I55, the lever I63 will be swung rearwardly and this movement of the lever will be communicated through the yoke I6I to the sliding keys 56 and thence through the ball bearing 55 to the sleeve 11 and clutch housing 49. The clutch housing 48, upon being moved towards the right in Fig. 1, causes the clutch for second gear drive to be placed in operative driving relationship, such drive being effected through the sleeve 14, gears 8I, 82, 81 and 88 as hereinbefore described.

When the selector valve is moved by the floating lever 30 to effect direct driving, the annular groove I43 of the selector valve sleeve I40 will be moved into alignment with the port I46. The fluid under pressure will then pass through the conduit I12 to the end of the right hand cylinder I66, shown in Fig. 4, and will cause the piston I65 thereof to be moved towards the left, thereby moving the lever I63 forwardly and causing the sliding keys 56 to be moved forwardly, said keys carrying with them the ball bearing 55 and actuating the clutch housing 48 so as to place the high gear clutch in driving relationship, the drive being effected directly from the engine to the driveshaft 52 in the manner heretofore described.

As will be seen from the showing of the selector valve in Figs. 5 and 8 of the drawings, as well as from the diagrammatic view of Fig. 19, when the annular groove I43 of the selector valve is in alignment with the port I44 for low gear drive, the ports I41 and I48 are in alignment with the ports I45 and I46 respectively, thus placing the cylinders and pistons for the second and high gear clutch in communication with the sump through the bore of the valve sleeve I42. When the groove I43 is in alignment with the port I45 for second gear drive, the port I 41 will register with port I46, and port I48 with port I44 to place the low and high gear cylinders in communication with the sump, while when groove I43 is in registry with the high gear port I46 the second gear port I45 will be in communication with the sump through the port I48 and as the lower end of the sleeve will have been moved entirely past the low gear port I44, communication to the sump for the low gear port I44 will be established around the lower end of the sleeve and through the hollow bore thereof.

REVERSE GEAR (Figs. 1, 10, 11 and 12) Reverse drive is effected by a purely manual operation and for this purpose the countershaft sleeve 83 is provided with a. gear. I80 with which is adapted to mesh an idler gear I 8| (see Figs. 10 and 11) slidably mounted upon a jackshaft I8I located below and between the countershaft 84 and the driveshaft 52. When said idler gear I8I .is slid into alignment with the gear I80 and with the gear 88, the reverse driving connection is effected. However, it is necessary first to disengage the gear 88 from the gear 81 and means are provided for sliding the gear 88 longitudinally out of mesh with the gear 81 and subsequently sliding the idler gear I8I longitudinally to cause said idler to engage with the countershaft gear I80 and also with the gear 88 of the driveshaft 52. This means comprises a. lever arm I82 suitably journaled in the side wall of the housing section 4| (see Fig. and having a shaft I83 projecting exteriorly of said housing section and to which any suitable manually operable lever may be secured. Projecting from the free end of the lever I82 is a pin I84 which engages within an elongated slot I85 formed in one end 01' a lever arm I86. The other end of the lever arm I86 is pivotally connected, as at I81, to the boss I88 of a sliding yoke I89, the

yoke I89 being mounted for movement longitudinally along a rod I90 suitably secured within the housing 4|. At a point intermediate of itsends, the lever I86 has pivotally connected to it, .one end of a connecting link I9I, the other end of which is secured to a second sliding yoke I92, also slidably mounted upon rod I98. The yoke I89 engages within a suitable groove I93 formed in the idler gear I8I while the yoke I92 is engaged within a similar groove I94 formed in the small rearwardly extending boss of the drive shaft gear 88.

In order to insure the demeshing of the gear 88 from the gear 81 before the idler gear I 8| is thrown into mesh with said gear 88, the yoke arm I89 is held in a position in which the gear I8I is inoperative by means of a spring pressed ball I95 (Fig. 12) which engages within a detent or groove in the rod I90. When the reverse gear shift is manipulated to place the reverse gears in operative engagement, the lever arm I82 is rotated in a counter clockwise direction (Fig. 11) so as to cause the upper end of the lever to move from the right to the left, as seen in this figure of the drawings. Due to the advantage of the lever arms, and also to the holding of the yoke arm I89 by the spring pressed ball I95, the first result of the movement of the lever arm I82 in the manner above described will be to cause the lever arm to swing upon the pivot I81 thereof, the spring pressed ball I95 tending.

to hold the yoke I89 against movement. A pull will therefore be exerted through the connecting link I9I upon the yoke I92, thus sliding the gear 88 to the left (Fig. 11) and disengaging said gear from the countershaft gear 81. After the gear 88 has been completely disengaged from the gear 8!, further movement of the gear 88 towards the left will be prevented by the face of said gear 88 coming in contact with the extended boss 8| a of the gear 8I. Continued movement of the lever I82 will result in transferring the pivotal point of the movement of the lever I86 to the connection of said lever with the connecting link I9I. The lower end of the lever I86 will then be moved from the left towards the right in Fig. 11, thus sliding the idler gear I 8I into engagement with the countershaft gear I88 and also into engagement with the teeth of the gear 88; The construction and arrangement of the levers I83-I86 and associated parts, are such as to insure not only the demeshing of the main shaft gear 88 from the countershaft gear 81, but also to insure.

countershaft gear I88, misalignment of the gear teeth may be corrected by imparting a slight ro- ,tation tothe countershaft gear I88 and idler I8I through the first gear clutch. 1

Vmnrom Srmn Govmnoa Connor.

"- (Figs. 1, 9. 19 and 21) The automatic controls for the selector valve havebeen briefly described "in connection with 5 diagrammatic showing in Fig. 19 of the drawings. As will be understood, the connection from the accelerator 34 to one end of the floating lever 38 may be made in any suitable manner. The end of the floating lever 38 with which the push rod 32, operated by the accelerator pedal, engages, is held up into contact with said push rod by means of a spring 32. )At its other end the floating lever 38 has a lost motion connection through the nuts and springs 35 with'the rod 35 which leads to thegovernor indicated generally by the reference character G in Fig. 19. Although any suitable type of governor may be employed, I prefer for compactness of construction, the use of a governor of the type shown in Figs. 1 and 9 of the drawings, and which consists of a pair of weights 200 and 28I mounted within an extension of the first gear clutch housing 93. Each of these weights carries a small roller 282, the peripheries of which engage with the inner walls of the governor housing 203,,as shown in Fig. 21. Each governor weight has a reduced portion towards its outer periphery that engages slidably between a pair of guide ways 283 formed in the interior of the governor housing 283. At their inner ends each weight is provided with a radially extending slot 284 within which the rollers 282 are rotatably mounted upon pins 202 which extend through the respective governor weights. Spanning each roller 282 is the yoked end of a curved connecting link 205, said yoked ends of the link 285 being apertured for engagement with the pins 282**. The other ends of the links 205 are pivotally secured by a pin 205 to a plug 286 slidably mounted within a sleeve 201 secured within a hollow projecting boss 208 of the governor housing 203.

v The inner end ofthe sleeve 201 terminates in an inwardly projecting flange which forms an abutment for one end of a spring 289, the other end of which spring abuts against an enlarged head 2IlIi of the plug 206. A second spring 2I8 encircles the plug 286 and cooperates with spring 289 normally to urge the plug 286 outwardly of the sleeve 201 and boss 288. The connection between the plug 206 and the connecting rod which leads to the floating lever 30 is effected through a small rod 2 seated within a bore formed in the end of the plug 286. This rod 2| I is mounted within a ball bearing 2 I2 and has a reduced threaded end which is screwed into a yoked connecting rod 2| 3, the rod 2I3 passing slidably, but non-rotatably, through a suitable packing gland 2M seated within the outer end of the sleeve 201.

The operation of the governor will be readily understood. As the main shaft gear 88 remains in mesh with the countershaft gear 81 for all conditions of forward drive, during which automatic operation of the transmission is effected, the sleeve 83 with which the gear 81 is formed integrally will always be driven at a rate proportional to the speed of the propeller shaft of the automobile, and, therefore, the speed of rotation of the sleeve 83 will always be proportional 7 to the vehicle speed. As. the clutch housing 93 is secured to the sleeve 83 and rotates in unison therewith, the clutch housing will also rotate at a speed proportional to the vehicle speed, and as the clutch housing 93 rotates, the weights 288,

2M of the governor will be caused to move under the influence of centrifugal force outwardly from the axis of rotation of the governor in an amount dependent upon the vehicles speed. The outward movement of the weights 200, 2M will be communicated through the plug 206 and rod 2I3 to the connecting rod 35, the connecting rod 35 being connected at its outer end to the floating lever 30 and causing the right hand end of the lever to be moved upwardly in response to'the increase of vehicle speed as indicated in the diagrammatic view in Fig. 20, thereby causing automatic shifting of the selector valve and a consequent effecting of first, second or third gear drive, as will be readily understood from a consideration of the diagrammatic view in Fig. 20 and from the foregoing disclosure.

The particular construction of the governor control as above described has marked advantages for use in connection with an automatic transmission of the type herein disclosed because of the simplicity and compactness of the structure, with the two weights 200, 2M, completely enclosed within a small housing and guided therein for simple in and out radial movement, thus enabling the simple reciprocating movement of the weights to be employed directly to produce the desired actuation of the floating lever 30 through the rod 35 without necessitating the use of any complicated system of links and levers such as are commonly used on centrifugal governors to obtain the desired differential action necessary to compensate for the rapid increase in centrifugal force at the higher speeds. It is to be noted that due to the angularity of links 205, the latter under the influence of the springs 209, 2I0 serve to pull the weights normally inwardly towards the axis of rotation, thereby to resist the outward movement of the weights under centrifugal force. Attention is called to the fact that the inner spring 2I0 is shorter and heavier than the outer spring 203, so that at the lower speeds the much feebler centrifugal forces resulting at such speeds are resisted by the outer spring 2I0, whereas, in the higher speed ranges, and greatly increased centrifugal forces resulting therefrom, both the outer and inner springs become effective to resist the outward movement of the weights 200, 20!, and cooperating to secure, what may be termed, a diflerential spring action.

A governor constructed in accordance with the above principles is therefore not only highly advantageous for use in an automatic transmission of the type herein disclosed because of its simplicity and therefore low cost of manufacture, but also on account of its compactness which enables it readily to be incorporated directly into the transmission housing, and in addition because all the moving parts thereof may be entirely enclosed within a small housing and completely sealed against access of road dust, dirt and grit.

In addition to the automatic shifting of the gears by the floating lever, the constructional arrangement of the pressure control valve and its associated parts is such that, as hereinbefore explained, the pressure control valve will be held normally in a position such as to cause the ports I21 and I28 to be closed, and to trap, as it were, the fluid pressure communicated to any cylinder and piston in accordance with the extent of throttle opening. And whenever the accelerator pedal is released the pressure existing within the chamber I26 and such cylinder and piston will cause the valve I23 to be moved to uncover the port I28 and thereby permit the trapped fluid to flow back to the sump and release the clutch then in engagement. The release of any of the clutches in this manner, 1. e., by the release of the accelerator pedal, therefore establishes a free wheeling condition, because it is not accompanied by the engagement of any other clutch, but all clutches being disengaged there will be under these conditions no driving connection between the engine and propeller shaft.

Fear: WHaELrNe LocKoU'r (Fig. 19)

The following means have been provided to render the free wheeling function inoperative when this may be desired:

The free wheeling lockout button 2 I is secured in any readily accessible location, such for example, as on the dash 2I6 of the automobile.

,This button is connected by means of a Bowden wire 2II, with a small stop or collar 2! placed in proximity to one of the lever arms of the bell crank lever I36. When the button M5 is pushed inwardly the collar 2 I 8 is moved into engagement with the bell crank lever I36 to move such lever into a direction such as to prevent the pressure upon spring I35 from being released when the accelerator pedal is released. The loading thereby being maintained upon the spring I35 will therefore be sufiicient to prevent the valve bushing I25 .from' opening the port I28 when the accelerator pedal is released. In order to, avoid stalling of the engine at low speeds or when bringing the vehicle to a stop, at such times as the free wheeling lockout is operative. automatic control and release of the free wheeling lockout may be effected at a predetermined desired speed by connecting the governor to the anchor 2 I 1*- of the tube of the Bowden wire 2II. This connection may comprise a rod 2H having a roller 2II at one end thereof for engagement with a notch formed in the extension of the governor connecting rod 35 and so arranged that when the vehicle has slowed down to such predetermined desired speed, the roller will drop into the notch on the rod 35 and thus permit the anchor 2I'I of the Bowden wire tube to move to the left, thereby permitting the stop 2I8 to move to the left and out of engagement with the bell crank lever I36, and thus unload spring I35.

SECOND GEAR BRAKE (Fiy- 19) As is well known, it is of course at times not only desirable, but sometimes essential, in traveling down a steep hill, for example, to keep the gears of the car locked in second drive in order I to use the braking effect of the engines compression. Means are provided in the present invention to accomplish this result, and such means comprise a manually operable button 220 (see Fig. 19) which preferably is arranged in any convenient position upon the floor boards of the car adjacent to the driver to be actuated by the driver's foot. The button 220 has connected to it a Bowden wire 22I which is supplied with a stop or collar 222, similar to the stop 2I8 for engagement with the bell crank lever I36, the stop 222 functioning in a manner similar to the stop 2I8 to prevent the pressure upon spring I35 from being released when the throttle is released, therespring I35 of the pressure control valveLPV thus insuring that the said valve willbe held open to permit the fluid to haw from conduit C to conduit C, and the bellnia'fik...lever223 will also be actuated by the stop 222 to push the selector valve down to the position for establishing communication to the piston and cylinder P2 for second gear drive.

It will thus be seen that when the button zzo" is depressed the second gear clutch will be held in operative clutching engagement and that the usual second gear braking effect may be quickly obtained whenever desired.

MANUAL OPERATION (Figs. 17 and 18) As it is sometimes desired that apositive clutch connection be effected when the engine is not in operation, such as in towing a car to start the engine, means have been provided to meet such a contingency. Such means may consist in employing, for example, mechanism associated with the ordinary emergency, or hand parking, brake lever for effecting a positive mechanical engagement of the direct or third gear drive. For this purpose the emergency brake lever 246 (see Fig. 18) is arranged to have a forward movement beyond its normal position for-disengagement of the emergency brake. As shown in Fig. 18, the emergency brake lever 246 is provided with the usual pawl 24I adapted to engage with the teeth 242 of the sector arm 243 for holding the emergency brake applied in the conventional manner. In addition to the teeth 242 the sector 243 is also provided with the teeth 244 with which is adapted to be engaged at second pawl 245 pivotally carried by the lever 246. The lower end of the lever 246 has slidably mounted thereon a block 246 which is normally in the position shown in full lines in Fig. 18. The block 246 is provided with an aperture 241 adapted, when the block is in its normal position, to stand in alignment with one end of a push rod 248, which rod extends into the housing section 4| and at its other end engages with the lever arm I63 which, it will be recalled, is connected with the yoke I6I for moving the sliding keys 56 and second and third gear clutches into engagement. In the ordinary automatic operation of the transmission by the fluid pressure system with the block. 246 in the full line normal position the movement of the lever I63 by the fluid pressure means will merely cause the outer projecting end of the rod 248 to pass freely into the aperture 241. When the emergency brake lever is used under normal conditions the block 246 will serve as a stop to limit the forward travel of said lever.

If it should ever become necessary to'effect emergency operation of the automobile by manually placing direct drive or third gear in operative engagement by mechanical. means, the block.

- 246 may be raised from the full line position gency brake lever 246 is moved forwardly to the dotted line position indicated, the block 246 will cause the rod 241 to push against the lever arm I63 moving said lever arm forwardly and thus causing the clutch for direct drive to be placed in operative driving relationship, the brake lever 246 being held in its extreme forward position by the engagement of the pawl 245 with the sector teeth 244, thereby holding the direct drive clutch and gear connection in operative condition as long as necessary or desirable.

TRANSMISSION SHAFT BRAKE (Figs. '1, 13, 15 and 16) The driving unit here disclosed may also include as a component part thereof a transmission brake which presents some novel features of construction. This brake comprises a hollow tubular brake drum 256, suitably secured to the end of the drive shaft 52, and with the periphery of which is adapted to be engaged a pair of brake bands 25I, 252.

These brake bands are in the form of semicircular halves, the ends of which are suitably secured to a U shaped bracket 253 in the sides of which are threaded four horizontal adjusting screws 251 and 258 bearing against the brake housing anchorage lug 259 as shown. There is also provided a vertical adjusting screw 266 threaded in lug 259 and projecting through bracket 253 as shown, a suitable spring 261 also being provided to normally urge the bracket 253 and brake band assembly upwardly thereby to facilitate adjustment of the brake.

The brake bands 25I, 252 are provided respectively with the extensions 25I and 252 which are carried beyond the vertical plane in which the center of the brake drum is located, and said extensions have secured to them the cam shoes 25l and 252 respectively. Located between the cam shoes 25I and 252 is the brake shoe actuating cam 254 connected to the brake operating shaft 255, which shaft is suitably journaled in a bracket secured to the brake housing and has fastened to When such brake lever is actu It is possible, with the above construction, to I so equalize the pressure on the two halves of the brake linings that the brake may be applied without creating sideways forces which would have to be balanced at the external supporting points of the housing. The adjusting screws 251 and 256 provide means for equalizing the clamping force applied by the two brake bands 25I and 252 and when this is accomplished, the tangential force at the upper anchorage 259 equals the tangential force adjacentto the shaft255 which. is also fixed and forms an anchorage. These two forces form a couple through which the braking force and the tendency of the drum to turn is resisted without producing any side force that would tend to deflect the shaft and its bearings. It is to be noted that this construction is a marked departure from a conventional brake unit consisting of one anchorage and a floating clamping pivot in which the braking torque isresisted by a couple consisting of the force at the anchorage 

